Improved drill-jar



UNITED STATES PATENT OFFICE.

CHAS. A. READ, OF LOGKPORT, NEW YORK.

IMPROVED DRILL-JAR.

Specification forming part of Letters Patent No. 51,217, dated November:28, 1865.

specification, in which- Figure I is an elevation of a set ofdrillingtools, such as are commonly used in boring oil or Artesia-nwells, with my improved jar connected therewith. Fig. II is an elevationof thejar disconnected and by itself. Fig. IIIis a longitudinal sectionof same and Fig. IV is across-section of same.

`My improved drill-j ar consists, essentially, of a cylindrical barrelconnected to the augerstem, within which is placed a vertically-movinghead or piston connected with the sinkerbar, which piston, in the upwardmovement of the drill-rope, strikes against the barrel-head and givesthe required blow or jar to the barrel and tools connected therewith, toloosen them, the moving piston being entirely pro- 4 tected within thebarrel as against any possible clogging or wedging of the same.

Letters of like nameand kind refer to like parts in each of the gures.

A set of boring-tools for sinking oil or other Artesian wells commonlyconsists of a centerbit, auger-stein, drill-jar, and sinker-bar, towhich the drill-rope is connected by a ropesocket, the jar being locatedbetween the auger-stem and sinker-bar. (See Fig. I.) E represents thecylinder or barrel of my improved drill-j ar, made of heavy wrought-irontubing of less diameter than the bore of the well, so thatit willmovefreely therein. It has a screw-plug and socket, f', at its lower end, bywhich it is connected to the auger-stem, and at its upper end ascrew-head,f2, bored for the passage of the piston-rod.

G represents the piston-head, forged upon the end of the piston-rod G',and tting the barrel E and moving snugly therein, the rod workingthrough the screw-headf2, and connected with the sinker-bar by ascrew-socketjf.

H H represent vertical slots cut in the cylinder diametrically oppositeeach other, in which a guide-pin, H', inserted through the piston-headslides, its office being to prevent the turning of the piston within thecylinder, so that the rotation of the drill-rope will be communicated t0the cutting-tool.

The operation of the jar is as follows: The length of the. drill-ropebeing so regulated that the drill or cutting-tool will strike before thewalking-beam or other operatin g device completes its downward motion,after such strikking of the drill a certain amount of slack.

in the rope will be produced, which will be taken vup by the weight ofthe sinker-bar, moving the piston downward into the cylinder, so that atthe next upward stroke the drill-rope, sinker-bar, and piston will movesome distance before lifting the drill and auger-stem, which will notmove until the piston strikes the cylinder-head.' It is the sudden blowor jar produced by this striking of the piston which loosens thecutting` tool (which by its previous blows will have become jammed ortight in the well) and saves the extreme expenditure of power, withdanger of breaking connections which would be required to liftit by adead pull.

The principal advantages of my improved jar over those in common useare- First, greater strength and durability, with less cost ofconstruct-ion.`

Second, a much greater striking-surface is obtained, and without thetendency to split and spread the jar, which exists in the common tool.In the common drill-j ar there is only one and one-quarterinch strikingsurface. In this there is five and one-half inches.

Third, the absolute protection of the moving or striking part, (t. e.,the piston,) by the cylinder or barrel, against any chance of wedging orclogging.

In the common form of jar, both parts vbeing alike, the striking part isliable tojam or wedge when the hole bored gets out of round orflattened, and then it can be loosened only by a dead pull, which willfrequently break the conncctions and leave the tools, or part of them,in

the well. This can never occur in my improved jar, since, howevertightly the barrel may become wedged,the piston will 'always be free tomove, and the blow or jar may be applied to loosen and free thecylinder, as well as to loosen and free the drill.

The blow of the commonjar has a constant tendency to split the link, andconsequently to widen and Wedge it in the well. My impiston G,including` the guide-pins H', pistonprovenlent Wholly avoids thisdifficulty. rod Gf, screw-plug and socketf, and screw- Having thusdescribed my invention, what headfz, substantially as set forth. Iclaim, and desire to secure by Letters Put- CHARLES A. READ. ent, isWitnesses:

Adrill-jar forArtesan-Well boring,consisting R. N. WILLIAMS, of the fullcylinder E, including the slots,v H, W. H. FORBUSH.

